docs: def _check_parameters(self):
          """Internal function to verify the basic parameters of the SOM.
          """
          if self._map_type != "planar" and self._map_type != "toroid":
              raise Exception("Invalid parameter for _map_type: " +
                              self._map_type)
          if self._grid_type != "rectangular" and self._grid_type != "hexagonal":
              raise Exception("Invalid parameter for _grid_type: " +
                              self._grid_type)
          if self._neighborhood != "gaussian" and self._neighborhood != "bubble":
              raise Exception("Invalid parameter for neighborhood: " +
                              self._neighborhood)
          if self._kernel_type != 0 and self._kernel_type != 1:
              raise Exception("Invalid parameter for kernelTye: " +
                              self._kernel_type)
          if self._verbose < 0 and self._verbose > 2:
              raise Exception("Invalid parameter for verbose: " +
                              self._kernel_type)